System information

Configuring Triggers and Alarms 153
Ethernet Frame Errors by Station
This trigger activates when there is an Ethernet frame error by station observed.
• “Hardware Address” dropdown—allows you to select the hardware address
(station) that you want to trigger on. These addresses are read from the address
table (see Filters section).
• “Percentage of error packets (0.01%)” spinbox—allows you to define the percent
of errors you want to trigger on.
• “Min number of packets (trigger level)” textbox—allows you to define the
minimum number of packets you want Observer to examine prior to considering
the condition a triggerable event. This allows you to avoid low traffic situations
where the percent of error packets may be quite high, but the total traffic to/from
that station is so low that, in essence, it is an idle period.
• “Time interval (seconds)” spinbox—allows you to set how long the trigger will
look at traffic and calculate the above conditions before resetting and starting over.
• “Error Type” option buttons—allows you to select the type of error you want
Observer to trigger on: CRC, Align, or Too Small.
• “Use current filter profile” checkbox—when selected, allows you to use the current
protocol filter.
Fragmented IP Packets
This trigger allows you to find fragmented IP packets and is used to find TCP/IP
devices that are not optimally configured (e.g., routers with MTUs that are set too
small) and devices that may be down (or are about to go down).
• “Number of fragments” textbox—allows you to set the number of fragmented
packets which activate the trigger.
• “Minimum number of packets (trigger level)” textbox—allows you to set the
smallest number of packets in an averaging period that will be provided as data for